High pressure studies of solid methane are performed using both classical simulated annealing and first-principles methods. A series of simulated annealing and geometry optimization reveal a monoclinic P21/b structure with the unit cell containing four methane molecules. The phonon dispersion curves and vibrational density of states indicate that this structure is stable in the pressure range 10-90 GPa. The electronic band structure and density of states show that this structure has not metalized until 90 GPa.
High pressure studies of solid methane are performed using both classical simulated annealing and first-principles methods. A series of simulated annealing and geometry optimization reveal a monoclinic P21/b structure with the unit cell containing four methane molecules. The phonon dispersion curves and vibrational density of states indicate that this structure is stable in the pressure range 10-90 GPa. The electronic band structure and density of states show that this structure has not metalized until 90 GPa.
ZHAO Juan;FENG Wan-Xiang;LIU Zhi-Ming;MA Yan-Ming;HE Zhi;CUI Tian;ZOU Guang-Tian. Structural Investigation of Solid Methane at High Pressure[J]. 中国物理快报, 2010, 27(6): 66101-066101.
ZHAO Juan, FENG Wan-Xiang, LIU Zhi-Ming, MA Yan-Ming, HE Zhi, CUI Tian, ZOU Guang-Tian. Structural Investigation of Solid Methane at High Pressure. Chin. Phys. Lett., 2010, 27(6): 66101-066101.
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